The European Commission, which enforces common policies of the EU's 27 member countries, adopted the rule “in order not to risk jeopardizing citizens’ health and safety.”

As a ProPublica/PBS NewsHour investigation detailed earlier this month [2] , X-ray body scanners use ionizing radiation, a form of energy that has been shown to damage DNA and cause cancer. Although the amount of radiation is extremely low, equivalent to the radiation a person would receive in a few minutes of flying, several research studies have concluded that a small number of cancer cases would result from scanning hundreds of millions of passengers a year.